The present invention relates to a quick-action on/off valve. More particularly, the invention relates to a valve which effects a quick-action opening of the line when the line pressure reaches a predetermined minimum, and effects a quick-action closing of the line when the line pressure drops below a predetermined minimum.
There are many applications wherein it is desirable to provide a valve which maintains the line closed until the line pressure rises above a predetermined minimum value, at which time the valve is to open with a quick-action; such valve is also to maintain the line open unless and until the line pressure drops below another predetermined value, lower than the predetermined opening pressure, at which time the value is to close with a quick-action. One application for such a valve is in systems for supplying irrigating water to rotary sprinklers, wherein the sprinklers require a minimum line pressure in order to produce proper operation, i.e. rotation of the sprinkler, minimum range of distribution of the water, and the like; thus, if the supply line is turned on when the line pressure is too low, the sprinklers will receive a supply of water but will not properly operate to distribute the water, thereby producing water wastage. Another application for such valves is in pulsating water supply systems, for example in greenhouse cooling, wherein proper operation of the system requires quick-action opening and closing of the line to produce each pulse of water.
An object of the present invention is to provide an on/off valve having advantages in the above respects and particularly useful in the above-mentioned applications as well as in other applications wherein quick-action opening and closing of the valve is required or desired.